Cosmic-ray-induced background intercomparison with actively shielded HPGe detectors at underground locations

摘要

The main background above 3 MeV for in-beam nuclear astrophysics studies with gamma-ray detectors is caused by cosmic-ray-induced secondaries. The two commonly used suppression methods, active and passive shielding, against this kind of background were formerly considered only as alternatives in nuclear astrophysics experiments. In this work the study of the effects of active shielding against cosmic-ray-induced events at a medium deep location is performed. Background spectra were recorded with two actively shielded HPGe detectors. The experiment was located at 148 m below the surface of the Earth in the Reiche Zeche mine in Freiberg, Germany. The results are compared to data with the same detectors at the Earth's surface, and at depths of 45 m and 1400 m, respectively.